Mammalian cancer is the sixth most common cancer among women in the United States and constitutes the forth cause of death. Because of its asymptomatic early stage and the lack of an effective early-stage detection test, this cancer is the most lethal among all gynecological malignancies. Mammalian carcinogenesis involves multiple genetic changes, revealed as alterations in the expression of certain genes, particularly those related to cell cycle regulations, such as the tumor suppressor genes p53, p16, and BRCA, and the oncogenes AKT2, ras, and c-Myc. Understanding the mechanisms of these changes could lead to using the genes as markers for the detection of mammalian tumors at an early stage. All previously known markers for cancer have certain drawbacks. Some stain only a small subset of malignancies, others do not allow to discriminate between the different pathological developmental stages of the corresponding disease, while others also stain not malignant tumors.
In 1993, a monoclonal antibody directed against candida krusei cytochrome c was shown to react with a cytoplasmatic fraction protein of human ovarian carcinoma cell line (Yasumoto K., et al., 1993, Hum. Antib. Hybrid 4:186 ff.). Independently, it was reported that Nab C6, generated against candida albicans mannoproteins, reacted specifically with a 43 kDa-molecule from a human mammalian carcinoma cell line, but not with non-neoplastic counterpart cells (Schneider J., et al., 1996, Br. J. Cancer 77:1015–1020).
To sum up, it has been known in prior art that molecular antibody C6 crossreacts with some carcinoma cells but the target remained to be elusive. Accordingly, it is an object of the invention to provide for a new marker which is useful for cancer diagnosis.